Intelligence warning of "near-term attacks that could either rival or exceed what we experienced on September 11" has led to another shift in the national terrorism rainbow. That'll mean tighter security for holiday travellers, including random vehicle searches at airports. No word on whether Tom Ridge plans to deploy Rover.
Seriously, though, if we did see holiday attacks that "rival" or "exceed" 9/11, would there be any political will whatever to hold the line on civil liberties? There's been a gradual return to sanity among many of the legislators who voted for PATRIOT, and moves to repeal provisions that threaten privacy without making us appreciably safer. An attack won't change the wisdom of those provisions, but it'd likely make that momentum evaporate.